非水库尔特法测定氯化钾、氯化钠结晶粒度

研究水溶盐结晶动力学需测定晶粒大小分布,作者使用新近发展起来的库尔特计数仪(Coulter Counter),结合电解质溶液的选择,成功地测定了氯化钾、氯化钠的晶粒。并对方法原理,非水悬浮剂选择,仪器定标及数据处理等进行如下讨论。一、原理使用英国产的TAⅡ型库尔特计数仪,又名16路多通道颗粒分析仪。测定方法是,先使待测物料均匀分散在电解质溶液中,借助负压,使微粒随溶液通过一小孔,孔两端各浸一铂电极,与检测系统构成闭合回路,其     

粒子计数仪在粘胶粒子测定的砬用

介绍了Multisizer3库尔特粒子计数仪的原理、使用方法，并着重介绍了粘胶纤维生产过程中如何使用Multisizer3库尔特粒子计数仪检测粘胶中的颗粒。     

在线颗粒物计数仪在自来水厂中的应用

介绍了生活饮用水中"两虫"的危害性和检测的必要性,颗粒物计数仪的计数原理,在"两虫"监测中的应用;颗粒物计数仪计在自来水厂中过滤和反冲洗过程、絮凝沉淀过程中的应用实例,以实现节能降耗、提高出水水质的目的。     

库尔特颗粒计数仪在油田水质分析中的应用

油田回注水中悬浮颗粒粒径中值是水质监测指标中的一项重要指标,库尔特计数仪是目前较为先进的粒径分析手段。文章对库尔特计数仪的检测数据进行了分析对比,找出了该仪器检测数据的一些特点和规律,并由此指出应用粒径中值数据分析和判断水质时应结合颗粒总数等数据,才能准确地判断水质的好坏。     

颗粒计数仪在北京第九水厂水处理中的应用

介绍了颗粒计数仪在水厂的使用效果，并论述采用该计数仪对于控制水质安全和优化工艺过程的必要性．对水厂的工艺过程改进有一定的参考价值。特别是对水质的优化监测．降低饮用水中致病原虫的风险将起非常重要的作用。     

颗粒计数仪在油田回注水中的应用

介绍了Multisizer3库尔特计数仪的原理、使用方法,研究了电解液、Kd值等因素对测定颗粒粒径的影响,运用多管交叠技术扩展了单管测量范围,样品的重复性测试取得了满意的效果.     

氯乙烯本体预聚合动力学和成粒过程的研究

对氯乙烯(VC)本体预聚合动力学和成粒过程进行了研究。通过称重法测定了VC预聚合阶段的转化率,同时研究了搅拌转速、聚合温度和引发剂用量对聚合动力学的影响。采用LS-230Coulter激光粒度仪测定聚合过程PVC粒子的体均粒径及其分布,考察了搅拌转速、聚合温度和引发剂用量对临界转化率和临界粒径的影响。根据实验结果并结合低转化率下VC本体聚合的微观成粒机理,提出了VC本体预聚合的成粒过程。     

一种分段式宽域粒度沉降分析仪的研制

0引言随着科技的发展,人们开发了多种基于不同工作原理的颗粒粒度的测量方法和测量仪器。最常见的有筛分法、沉降法、Coulter法和激光散射法等。筛分法只适用于粗粒度的测定,70μm以下的筛分就十分困难;Coulter法操作条件苛刻,只适于电解质中悬浮的粉体;激光散射法则有价格昂贵、调整困难、分辨率低和操作复杂等缺点。因而在工业上最常见的是沉降法〖1〗。上世纪80年代以来,我国相继开发了几种光透式沉降粒度分析仪,使我国沉降粒度分析水平得到了长足的发展。配合离心机的沉降粒度分析仪的测量范围通常在0.03～300μm,实际测量中设定的测量…     

显微镜与血细胞计数仪在血小板计数中的检测作用与影响

目的探讨显微镜与血细胞计数仪在血小板计数中的作用及其影响。方法对198例来院就诊体检人员进行血小板计数统计。结果正常标本计数无明显差异性(P>0.05),脂血标本和溶血标本计数比较,有明显的差异显著性(P<0.05)。结论显微镜与血细胞自动计数仪都是血小板计数的重要检测方法,在检测中重视2种方法影响和优势,对数据谨慎分析,确保检测结果的可信度和准确性,对临床治疗和用药提供有效的指导作用。     

切割泵对粘胶溶解及性能的影响

根据粘胶的溶解机理。在QB110C切割泵的作用下，通过考尔特ZB型粒子计数仪和电子显微镜（TEM）图片，分析了粘胶的粒子数和形态的变化。讨论了切割泵对粘胶溶解性及纺丝的影响。     

Crystal Size Measurement: Comparison of the Techniques of Sieving and Coulter Counter

Carefully sieved crystals of nickel ammonium sulphate are analysed with a Coulter particle size counter. Simple correction factors are proposed to rationalize the two sizing techniques.     

The Assessment of a New Range of Large Monosized Polystyrene Spheres and their Potential as Calibration Material for Particle Size Analysis Equipment

Large polystyrene spheres (nominally 5-, 7-, 10-, and 15-μm diameter) form a new range. The spheres have been sized using a Magiscan Image Analyzer, a scanning electron microscope, and a Coulter counter. Spheres of each nominal size have been found to have a tight size distribution.     

Size analysis of polymer latex powder. Comparison of results obtained by means of the I.C.I.–Joyce,Loebl disk centrifuge,the coulter counter,and the electron microscope

The volume frequency size distribution of PVC latex powder was determined by means of three different methods, which all gave the same frequency maximum at about 0.8–0.9 μ diameter. While the electron microscope analysis, which allows the agglomerates to be resolved into individual primary particles, did not show any particles above 1.5 μ in a sample of 9000, both the Coulter counter and the disk centrifuge showed a considerable amount of larger particles.     

超细粉体粒度测试方法浅析

介绍了超细粉体粒度测试的几种主要方法(激光衍射散射法、离心沉降法、颗粒图像处理仪和库尔特颗粒计数器)的测试原理及性能特点，并进行了比较。讨论了粒度测试中应注意的几个问题，重点分析了测试条件不同对粒度测定的影响，得出分散介质、分散剂、超声功率及超声时间等是影响粒度测定的最主要的因素；指出了重复性、真实性、易操作性、量程和动态范围是评价粒度仪测试性能的几个重要指标。     

The kinetics of titanium dioxide agglomeration in an agitated liquid suspension

The agglomeration of two TiO₂ pigments (0.2-1.0μ) dispersed in an agitated 1% saline solution has been studied by a sequential count method using a Coulter counter. A model based on collision frequency due to the turbulent motion in a stirred vessel predicts the second order rate constant k to be proportional to agglomerate volume and to stirrer speed to the power 3/2. Experimental values of k were proportional to threshold volume to the power 0.79, stirrer speed to the power 1.3, and independent of TiO₂ concentration     

Light transmission instrument for particle size analysis of colloidal dispersions

A simple light transmission instrument is described which enables average droplet sizes to be determined quickly and accurately. Light scattering is minimized by the use of a small-divergence laser beam and pinhole detectors, and by situating the sample photodetector relatively far from the sample. Good signal stability is ensured by the use of a double-beam configuration, the second beam serving as reference. The transmission of the sample is obtained from the time average ratio of the two signals. Use of a linearly polarized laser further increases accuracy and stability.Results of experiments with particles in the size range 0.8 – 50 μm show good agreement with Coulter counter analyses.     

Aggregation and Precipitation Kinetics of Canola Protein by isoelectric precipitation

Kinetics of aggregation, nucleation and growth of canola protein particles were developed in a 100 mL mixed-suspension mixed-product removal precipitator (MSMPRP) using isoelectric precipitation with HCI at pH 4.2. Protein yield in terms of total nitrogen was measured by Kjeldahl system. The size distribution of protein aggregates was determined by a Coulter counter. The effects of pH, protein concentration driving force, mean residence time, agitation rate, ionic strength of the solution, and the operating temperature on the size distribution and yield of protein particles were investigated. Population balance on the protein particles was used to derive empirical correlations for the index of aggregation, nucleation rate of primary particles and growth rate of protein aggregates.     

The surface area of bulk poly(vinyl chloride)

The porosity of poly (vinyl chloride) (PVC) resin particles produced in bulk polymerization is sensitive to polymerization conditions. Using scanning electron microscopy, 60μ spherical beads of PVC are shown to be composed of loosely packed 1μ spherical subparticles. This complex morphology is characterized by a variability in surface area. The surface area of bulk PVC materials can be measured by a chromatographic technique. The elution time of n-octane as a probe molecule on PVC packed columns is simply related to PVC surface area. At approximately constant particle size (measured by Coulter counter and optical microscopy), surface areas measured by argon adsorption are correlated to chromatographic elution times. The bulk density, plastisol viscosity and pore volume (from mercury penetration porosimetry) are determined and related to specific surface area.     

Cotton dust particle size distribution in oil mills

Analytical procedures have been developed for characterizing the size and shape of cotton dust particulates collected by the vertical elutriator (VE) sampler. Data are reported for dust distributions on VE filters collected from different processing areas (cleaning, delintering, hulling, and baling) in cottonseed oil mills. Results of particle volume distributions obtained with a Coulter counter are compared with data obtained from an image-analysis system designed to classify cotton dust into fibrous and nonfibrous (particulate) components. The image-analysis data include distributions of the lengths and widths of fibers and the areas and diameters of particles present on the VE filters. In many of the locations studied, a considerable amount of the total dust sampled can be attributed to lint, lint fragments, and also to particles significantly larger than 15 μm diameter. Southern Region, SEA, USDA.     

The influence of porosity of discrete particles upon their apparent dimensions as measured by the Coulter principle

Highly porous particles furnish, due to their porosity, smaller Coulter diameters and Coulter volumes than the real particle size and envelope volume, respectively. Finding a relation between these variables (eqn. 4) makes the determination of the latter easier. In addition to the readily obtainable Coulter and porosity data, only one empirical constant for each material class has to be determined.